If you know what's going to happen with the market, then you can really be a lead trader. But in this world, there's no perfect prediction so lead traders can always make mistakes with the current market. There are just too many variables that would affect the current condition. It's everyone's ball game.
Are you a lead trader? If you are, what is the best crypto exchange you can be a lead trader and what is the maximum profit in percentage?
In terms of having the best crypto exchange, I think you would select the one that has the least fee per trade so you can get the most out of your trades. In general, it's just the same as long as you are trading in the correct way.